5 mins" would be appropriate unless you are expressing it as an adjective then use the singular form, as in a five minute break or the ten minute mark. However, in scientific writing, the abbreviation for the units is always in the singular form – 5min, 5km, 5kg. It might therefore not be considered wrong to use singular forms of abbreviations with plural numbers.

Understanding the Context

PGA Tour: David Kocher betting profile: BMW Charity Pro-Am presented by TD SYNNEX David Kocher returns to the BMW Charity Pro-Am presented by TD SYNNEX, set to take place June 5-8 at Thornblade Club in Greer, South Carolina. Kocher will look to improve upon his previous ...